Printing mechanism with magnetic selection means



Jan. 7, 1969 K. KUPFMULLER 3,420,349

PRINTING MECHANISM WITH MAGNETIC SELECTION MEANS Filed July 28, 1967 INVENT OR KAR L KUPFMULLER AT'TO NEY United States Patent K 59,922 US. Cl. 197-14 6 Claims Int. Cl. B41j 23/38 The present invention relates to an arrangement for elfecting the mechanical distribution of bodies of the same kind on different tracks on account of a magnetic marking.

The feature of providing bodies which are being moved along certain tracks, for control purposes, with magnetic markings, isalready sufficiently known e.g. in the field of pneumatic tube engineering. The magnetic marking effects the generation of control signals which in turn serve to actuate magnetic switches or deflectors arranged along the track.

In cases where a plurality of bodies are arranged in a close succession and travel at a high initial velocity, they are supposed to be capable of being distributed randomly out of the continuous movement to various tracks. The principle of employing mechanically moved switches or deflectors is not practical, because the mass inertia problems arising as the transit time becomes shorter have a restrictive effect.

The arrangement according to the present invention avoids the use of mechanically actuated switches and the problems linked thereto. In addition, the cost for control means is reduced to a minimum. This is accomplished by the arrangement in that the bodies to be distributed are provided with extension pieces of a magnetically hard material which, in the course of their movement, are capable of being magnetically marked selectively by the action of electromagnets. The thus marked extension pieces thereupon enter a stationary magnetic field within which there is effected the distribution to the individual tracks.

In this arrangement the magnetic marking directly provides the forces by which the bodies to be distributed, are directed or guided into the predetermined track.

One particularly advantageous use of this arrangement is in mechanical printing mechanisms, wherein the types are arranged in an annular or ring-shaped fashion and which, out of the rotating movement, are caused to strike a stationarily arranged platen.

In connection with such a type of printing mechanism, the arrangement according to the invention will be described hereinafter, with reference to the sole accompanying drawing.

The printing mechanism as shown in the accompanying drawing is a perspective which, in a rear view, relates to an already proposed arrangement of a type-lever printing mechanism application Ser. No. 624,527 filed Mar. 20, 1967 by M. Fleischer and F. Galasker. In this case the annularly arranged type-levers 1 which, in the normal position, are directed radially towards the outside. The type levers constitute a plate-shaped ty-pe-lever magazine rotating below the platen 3 and around the vertically standing axis 4 at a uniform speed in the direction indicated by the arrow A. Via a toothed gearing, each typelever 1 is in a form-locking connection with a transfer lever 2 which, at their free ends, are provided with an extension 2a having a shuttle-shaped cross-section. These extensions 2a are moved in the normal condition on a circular track extending above a cam-shaped track 5. For printing a predetermined type, the associated transfer lever 2 or the extension 2a respectively, must be deflected to such an extent of the normal track of rotation, as to 3,420,349 Patented Jan. 7, 1969 come into engagement with the lower edge of the camshaped track 5 which, on account of its pitch, causes the associated type-lever 1 toeifect the printing by striking the platen. The platen is arranged so that during the time of the printing the relative movement between the stationary recording medium and the continuously moved type-lever is negligibly small. Another (not shown for purposes of clarity) cam-shaped track causing resetting of the type-lever to the normal position.

The greatest problem with respect to such a type of printing mechanism is toeffect, at full speed, the individual deflection of the selected type-levers 1. This must be accomplished with suflicient reliability because for a conventional selection there are only available fractions of one millisecond. These difiiculties, however, can be mastered with the aid of the inventive type of arrangement.

As can be recognized from the drawing a control magnet 6 is arranged in the direction of rotation following the not shown reset cam. This control magnet 6 is passed over at a slight distance by the extension portions 2a of the transfer levers of the course of performing their rotational movement. The extension pieces 2a consist of a magnetically hard material which, depending on the instantaneous polarity of the magnet 6 existing in the moment of passage, are given a corresponding polarized magnetization. Subsequently to this magnetization and in the course of their normal rotation track, the magnetized extension pieces 2a enter the range of two oppositely arranged permanent magnets 7 and 8 having opposite polarities. These magnets 7 and 8 are, with respect to the total circumference of the type magazine, relatively long and follow the track curvature of the extension pieces 2a including the beginning of the curved or cam-shaped track 5. The initially small spacing between the magnets 7 and 8 is enlarged to a finite opening width which, within the overlapping range with the cam-shaped track 5, provides an interspace or distance corresponding to the maximum thickness of the extension pieces 2a above, as well as below the track 5.

During the continuous rotation, the extension pieces 2a are normally given a magnetic orientation which, within the field of the permanent magnets 7 and 8, causes a deflection of the extension pieces 2a in the upward direction, so that they are retained on their normal track of rotation. If one type, however, has been selected for printing then, under the control of suitable synchronizing means, the magnet 6 is subjected to a polarity reversal for the period of time in which the selected associated extension piece 2a is positioned within its range of action. The respective extension piece 2a, during the subsequently following passage between the two permanent magnets 7 and 8, is subjected to a corresponding gradual deflection in the downward direction corresponding to the slight inclination of the magnet 7. This causes, in accordance with the shown extension piece 2a the engagement with the lower edge of the curve-shaped or cam shaped track 5. The engagement between the type-lever 1 and the transfer lever 2 is made so that the lever 2, within the range of deflection of the magnets 7 and 8, is freely moveable with respect to the associated type-lever. This permits smaller magnetic setting forces since they only have to correspond to the mass of the transfer levers 2 which is made small. The pitch of the cam-shaped track 5, via the deflection of the associated transfer lever, effects the lifting of the selected type-lever 1 which, shortly after the end of the track 5, almost vertically strikes the opposite side of the platen 3 in the course of its free flight. During rebound, the associated transfer lever 2 with its extension piece 2a already enters the range of the not shown reset cam, whereby the type-lever is reset to normal. The extension piece 211, in the course of the continuous rotation of the type magazine, enters the range of action of the magnet 6 again, and is now remagnetized into the previous magnetic orientation condition unless the same type is selected to be printed again.

While I have described above the principles of my invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of my invention as set forth in the objects thereof and in the accompanying claims.

What is claimed is:

1. printing mechanism comprising:

a platen located in a horizontal printing plane;

a plurality of annularly arranged type-levers which, in

a normal position, are directed radially towards the outside, said type-levers constitute a plate-shaped type-lever magazine rotating below said platen and around a vertical axis;

a plurality of transfer levers, each lever being in a form-locking connection with one of said type-levers at the end normally closest said axis of rotation;

a plurality of extension pieces, each piece being magnetizable and located on the free end of one of said transfer levers;

a circular cam-shaped track having an upper and lower edge, said extension pieces positioned to move, in a normal condition on a circular track extending above the upper edge of said cam;

electro-magnet selection means for magnetically polarizing said extension pieces; and

magnetic deflection means in the path of said extension pieces for deflecting, in response to the magnetic polarization, said extension pieces from a normal track rotation into rotational engagement with the lower edge of said cam,

whereby the lower edge of said cam-shaped track effects the lifting of a selected type-lever to effect the printing by striking the platen.

2. A mechanism according to claim 1, wherein said magnet deflection means includes a stationary magnetic field which is constituted by two oppositely polarized permanent magnets.

3. A mechanism according to claim 2, wherein said two magnets are positioned in the path of rotation of said extension pieces and form an opening of slight inclination, and the beginning of said circular cam-shaped track is formed as a wedge which projects in overlapping fashion into the free angular space of said opening.

4. A mechanism according to claim 3, wherein said electromagnet selection means is a control magnet positioned so that said extension pieces pass over the control magnet whose instantaneous polarity gives the desired magnetic orientation to said extension pieces for sensing by said deflection means.

5. A mechanism according to claim 4, wherein between said type-levers and transfer-levers there exists a clearance corresponding to the deflection stroke.

6. A mechanism according to claim 5, wherein said extension pieces have a shuttle-shaped cross-section.

References Cited UNITED STATES PATENTS 904,743 11/1908 Weston l97l4 2,613,796 10/1952 Prouty 197-12 3,200,933 8/1965 Schenk et al. 198-38 3,214,003 10/1965 Wilson 198-38 3,307,162 2/1967 Fink 198-38 X 3,355,001 11/1967 Reed et al 197-12 X ROBERT E. PULFREY, Primary Examiner.

EDGAR S. BURR, Assistant Examiner.

U.S. Cl. X.R. 

1. PRINGING MECHANISM COMPRISING: A PLATEN LOCATED IN A HORIZONTAL PRINTING PLANE; A PLURALITY OF ANNULARLY ARRANGED TYPE-LEVERS WHICH, IN A NORMAL POSITION, ARE DIRECTED RADIALLY TOWARDS THE OUTSIDE, SAID TYPE-LEVERS CONSTITUTE A PLATE-SHAPED TYPE-LEVER MAGAZINE ROTATING BELOW SAID PLATEN AND AROUND A VERTICAL AXIS; A PLURALITY OF TRANSFER LEVERS, EACH LEVER BEING IN A FORM-LOCKING CONNECTION WITH ONE OF SAID TYPE-LEVERS AT THE END NORMALLY CLOSEST SAID AXIS OF ROTAITION; A PLURALITY OF EXTENSION PIECES, EACH PIECE BEING MAGNETIZABLE AND LOCATED ON THE FREE END OF ONE OF SAID TRANSFER LEVERS; A CIRCULAR CAM-SHAPED TRACK HAVING AN UPPER AND LOWER EDGE, SAID EXTENSION PIECES POSITIONED TO MOVE, IN A NORMAL CONDITION ON A CIRCULAR TRACK EXTENDING ABOVE THE UPPER EDGE OF SAID CAM; 